Azo dye.



UNITED STATES PATENT OFFICE.

AR'1HUR ZART, F VOHWIN-KELJ, NEAR ELBERFELD, GERMANY, ASSIGNOR FAR- BENFAIBRIKEN VORM. FRIEDB. BAYER 8500., 0F ELBERFELD, GERMANY, A COR- PORA'IION OF GERMANY.

1,032,797; No Drawing.

of philosophy, chemist, citizen of the Ger:

man Empire, residing at Vohwinkel, near Elberfeld,Germany, have invented new and I useful Improvements in New Azo Dye, of

till

which the following is a specification.

My invention relates to the manufacture and production of new disaz'o coloring matters having 'most probably the following general formula:

soaul e -5N H R and R, meaning arylcarbonyl-EZ-amino-zi-- naphthol-7-sulfonic acid, such as benzoylo1 anisoyl-2-amino-5-naphthol-7-sulfonic acid, etc. Of course two different molecules of these compounds can be used. The dyes are obtained by combining two molecules of diazotized Q-amino-aryl-carbonyl-amino5- naphthoL'Y-sulfonic acids with the symmetriczcill urea of 2.5.7-amino-naphthol' sulfonic aci The new dyes are after being dried and pulverized in the shape of their alkaline salt. reddish powders easily soluble in water. They yield upon reduction with staimous chlorid and hydrochloric acid an aminoarylcarbonyl 2-amino-5-nap1ithol-7-sulfonic acid and the urea of 2.6-diamino-5-naphtliol- 7-sulfonic acid. "lhey dye cotton orange to red shades which can be combined on fiber with diazot-ized para -nitra ni lin from orange red to scarlet shades being thus obtained which are fast to washing and can be discharged to a good white.

In order to-illustrate the new process more fully the following example is given, the parts being by weight :7l6 parts of Q-paraaminobenzoylamino- 5 naphthol 7 -sulfonic acid are diazotized and the resulting diazo compound is combined with a solntionpf 504 parts of the synnnetrical urea of 2-amino-5-naphthol-7-su1fonic acid containing an excess of sodium acetate. W hen the combimitioo is complete the prodnot of the reaction is slowly rendered alkaline hy the addition of sodium earhonale;

AZO DYE.

pecification of Letters Patent. Patented July 16. 1912. Application filed June a, 1911. Serial No. 631,554.

it is then heated and the disazo dye is salted out. It is after being dried and pulverized in the'shape of its sodium salt a dark reddish powder, soluble in water with an orange color and soluble in concentrated sulfuric acid with a bluish-red color. By reduction with stannous chlorid and hydro chloric acid the dye is decomposed, .2-para a-minobenzoylamindf) naphthol 7 -=sulfonic acid and the symmetrical urea of 2.6-dian1- in'o-5-naphthol-T-sulfonic acid are obtained. It dyes cotton orangered shades, changing into a pure yellowish-scarlet by development with diazotized para-nitranilin. The shade thus obtained is fast to washing and can be discharged to a purewh-ite with bydrosulfite.

The disazo dye obtained from Qemetaaminobenzoylamino 5 naphthol- '7 -sulfonic acid dyes cotton orange-red yielding ascarlet by developing the dyed fiber with diazotized para-nitranilin. 011 using meta-aminopa ra-anisoyLiZ-amino-5-naphthol- 7 -sulfonic acid somewhat more bluish shades are obtained.

1. The herein described new disazo dyestuffs having most probably the formula:

(R and li meaning 2-arylcarbonylamino-5- naphthol-T-sulfonic acid) which are after being dried and pulverized in the shape of their alkaline salts reddish powders easily soluble in water: yieldingupon reduction with stannous chlorid and hydrochloric acid.

an aminoarylcarlnmyl-Q-amino-5-naphthol-7- sulfonic acid and the urea of 2.6 dianiino- 5-naphthol-7-sulfonic acid; dyeing cotton orange toured shades which can be combined on fiber with diazotized para nitranilin from orange-red to scarlet shades which are fast to washing and can be discharged to a pure white. substanti lly as described.

2. The herein described new disazo dyestutl' having most probably the formula:

(It meaning lbenzofilan-iiii'o-5-naphthol-T- sulfonic acid) which is after being dried and let by development with diazot-i-zed parapulverized in the shape of its sodium salt a nitranilin which are fast to washing and can dark reddish powder, soluble in water with be discharged to a pure white with hydroan orange color and soluble in concentrated sulfite, substantially as described. 15 5 sulfuric acid with a bluish-red color; yield- In testimony whereof I have hereunto set ing upon reduction with stannous chlorid my hand in the presence oftwo subscribing l0 7-sulfonic acid; dyeing cotton orange-red shades, changing into a pure yellowish scar- ALFRED HnN-KE ALBERT F. NUFER.

and hydrochloric acid Q-para-aminobenzoywitnesses. lamino-5-naphthol-7-sulfonic acid and the ARTHUR ZART. [1 s.]-' symmetrical urea of 2.6-diamino-5-napht-hol- Witnesses:

Copies 01 this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

v Washington, D. G. 

